Rewriting The Past
by truewinchester168
Summary: Taken from the Dursley's at only 8 years old, Harry Potter is taught Magic by Merlin himself until his 16th birthday. On that day he will fulfill a destiny. When he is sent back in time to the days of Camelot can he rewrite history and save the kingdom? Full summary inside. Dumbledore Bashing. Merthur. Morgana/Harry
1. Prologue

_AN: Hey guys. This is my first fan fiction and I honestly have no idea where the idea came from. I was re-watching Merlin this afternoon and it just came at me out of the blue. It's a Harry Potter – Merlin Crossover and I'm extremely pleased with the idea. As I know you'll all notice, I have made a few changes to the Merlin world. First off, Gwen and Arthur were never together. He is not interested in her and she is not interested in him. This is, for all intents and purposes, a Merthur fic. Also, Uther is not as….unreasonable at times as he should be. This may not be apparent at first but it will become apparent as the story continues. Anyways, I hope you enjoy and please remember to review._

_True Winchester_

Summary: On Harry's eighth birthday, he is visited by an older boy with black hair and flashing golden eyes. The boy introduces himself as Merlin Emrys and tells him that he needs his help. Wanting to get away from the Dursley's, Harry goes with Merlin willingly. They travel to the spot where Camelot once lay and Merlin makes a home for them there. For the next eight years, Merlin teaches Harry everything he knows about Magic. On his sixteenth birthday, the two boys re-enter the Wizarding World for one last time. The Savior's return has everyone up in arms but Harry and Merlin do not stay long. They stay only long enough to make absolutely certain that the world knows Albus Dumbledore's wrongdoings before travelling into the past. Harry arrives next to Merlin in Gaius' quarters with only a letter from Merlin himself and his wand. His mission? To change the future of Camelot. Can he save Camelot? Or will he fail?

**Prologue**

_Number Four Privet Drive_

_Ten O'clock p.m._

"DURSLEY! If you don't open this bloody door, I will blast it open!"

The sound of the boy's voice echoed through the empty street, causing several people to open their doors curiously. It had come from a tall, slender boy with black hair. He stood on the doorstep of Number Four Privet Drive, one hand placed firmly on his hip and the other pounding on the door. After a few moments, the door opened to reveal a rather large man in the most ridiculous looking night clothes. His walrus-like face was quite red and he looked as though he'd like to strange the boy on his doorstep.

"Who the hell are you?!"

The boy smirked, stepping inside the house with ease. "My name is Merlin. Merlin Emrys."

"What do you want? And get out of my house!"

"I'll leave as soon as you give me what I came here for you great prune."

"I don't have anything of yours. And if you don't leave I'll call the police."

Merlin laughed. "Oh do shut up Dursley. The police can't do anything to me. Now go retrieve your nephew from under the stairs."

"What do you want with him? He's just a freak."

The boy's eyes flashed golden as Vernon Dursley went flying into the wall. When he next spoke, Merlin's voice was low and dangerous.

"You will not call him a freak again. Now retrieve him before I spill your guts onto your floor."

The man gulped and ran towards a small cupboard. He came back a few minutes later holding the arm of a tiny boy with black hair and striking green eyes. Merlin strode forward and grabbed the boy gently, glaring all the while at the large Dursley.

"We're leaving now. Tomorrow morning you will be visited by a man named Albus Dumbledore. He will ask you what happened to young Harry here. When he asks his question, you will tell him that Merlin Emrys has claimed him and that his assistance is no longer needed. Are we clear?"

"Yes." The man muttered, gulping again.

Merlin nodded and turned to Harry. "Come Harry. We're going to go home."

The young boy nodded as Merlin hissed a few words in an ancient language. As soon as the words had left his mouth, the two had completely disappeared from sight. They arrived in front of an ancient looking castle and Merlin couldn't help but to laugh at Harry's wide eyes as he led the young boy into the palace. Despite its ruined exterior, the inside of the castle was beautiful and Harry was speechless with wonder as he stared around at the palace. Merlin led them to a large room and sat Harry down on a comfortable chair.

"Who are you?" Harry asked finally, staring in wonder at the older boy.

Merlin smiled. "I am known by many names young Harry but you can call me Merlin."

"Are you a…wizard?"

"I am. And so are you. That's why I've brought you here. I'm going to teach you magic. Magic of all sorts."

The little boy's eyes lit up. "Really? Oh that would be wonderful."

"Really. We'll get started in the morning. First, I think you need to sleep. This is my bedroom but you'll be sleeping here tonight. Tomorrow, I'll let you pick your own room before we start your studies."

"That's wonderful. Thank you ever so much sir."

Merlin smiled gently, leading the small boy over to a large, four poster bed. He tucked him in and kissed his forehead before climbing in on the other side. He'd need sleep as well. By the time morning came he and Harry would have a lot to do. Merlin fell into sleep easier than he had in almost a thousand years, knowing that he had everything he'd been waiting for within his grasp.

_**Hogwarts**_

Albus Dumbledore was beyond furious. He had tried so hard to keep the boy within his grasp and he'd failed. Harry Potter was their last hope, _his _last hope, and he'd lost him. Lost him to that bloody Mage. Bloody Emrys had won. Albus grabbed his bottle of Fire Whiskey and downed half of it in one swallow. He was so angry he couldn't speak. This was not supposed to happen. Harry was supposed to stay with his Muggle relatives until he was eleven years old when Hagrid would rescue him and bring him to Hogwarts. Harry would grow up enamored with Albus, wanting nothing more than to please him. This…this was a serious wrench in that plan and Albus had to do something to stop it. But what…what could he do? He downed more Fire Whiskey, thinking about what he must do. When the idea came to him he almost couldn't believe it. The old man smirked, pleased with his plan, and called for Severus Snape. He had things to do…

_**End Hogwarts**_

Merlin and Harry woke up at seven the next morning, refreshed and eager to start the day. As he was preparing breakfast, Merlin allowed Harry to sit behind him. The young boy asked many questions and the old Mage had to smile as he answered them. Harry asked him about his life, about magic, about so many things it made his head spin but he answered them all with ease. After all, this boy would change his past someday. The Mage was putting their breakfast on the table when a very angry friend marched into the kitchens. Severus Snape had befriended Merlin whilst attending Hogwarts. The man was – admittedly – a bit Dark but he was loyal. Loyal to Merlin himself even though Albus Dumbledore thought different.

"What is it Sev?" Merlin asked, raising an eyebrow as the young Potions Master threw his hands in the air exasperatedly.

"I'm going to bloody kill Albus Dumbledore."

"I'd advise against that, Severus. You may get thrown in Azkaban for that one."

Severus glared. "He's lost his mind. He wants me to track you down and bring Harry back to the Dursley's."

Merlin let out a laugh, shocking both Harry and Severus. He laughed until tears streamed down his cheeks. When he'd gotten a hold of himself, Severus calmly asked him what the bloody hell he'd ben laughing at.

"The fact that the man actually thinks he has a chance against me. I am by no means a conceited man…that was Arthur if you remember the stories I told you both…but I am over a thousand years old. I've been using magic longer than his entire family has been around. The man is puny and insignificant and he has absolutely no chance of beating me. My God is he that stupid?"

Severus smirked. "Seems he is. What're we going to do?"

Merlin grinned. "You're going to help me, of course."

Warily Severus asked, "How?"

"Simple. You'll keep up your fake search for me whilst helping me teach young Harry here. I've never been all that great at Potions I'm afraid. That's why Gaius was in charge of those."

"Eventually he's going to get suspicious, Merlin."

"Probably. But he'll have nothing he's able to prove. Besides, we're the only people that know where this is. I hid Camelot surprisingly well."

"When should we start teaching Harry, then?"

"We're starting today. We only have eight years before he goes back."

"All right then. Are you both ready?"

Harry grinned, speaking up for the first time. "Yep. Soon as Merlin is."

Merlin smiled, leading the way up to a large room. It had once been Gaius' rooms but now it would be where Harry learned. Severus shut the door behind them and Merlin muttered a few spells, cleaning the dust out of the room easily. He hadn't been in here in a few centuries. Too many memories here. He shook himself out of his thoughts as the boy's first lesson began…

_AN: There it was. The Prologue. Normally I won't have two Author's Notes on one chapter but I'm making an exception here. The next chapter we're skipping to when Harry is thirteen years old. Hope you liked it and remember to review._

_True Winchester._


	2. Chapter One

_AN: Hey guys! Here's Chapter One for you. Right now Harry is 13 years old. He's been with Merlin for five years exactly. It's through his point of view. Anyways, I hope you like it and remember to review. You guys are the best! I couldn't ask for better readers. _

_True Winchester._

**Chapter One**

_Harry_

If there was one thing I've learned from living with Merlin for the past five years it was that the man was nearly insane. Brilliant. But completely insane. I was used to some of his insane tendencies (such as the one where he liked to hang out miles below the castle where Kilghara used to live) but this one completely took the cake. He wanted me to finally meet the thousand and some odd year old dragon that had first told _him _about his destiny. Which meant we had to wake up at 4 in the bloody morning and travel 30 miles _on foot_ to the spot where he and the dragon met up once every few years. Why was this insane, you ask? Simple. I was walking 30 miles to meet a _dragon_.

"You know I'm pretty sure most teenage wizards aren't accustomed to meeting thousand year old dragons, Merlin."

He grinned. "Lucky thing you're not a typical teenage wizard then."

"I now see why Arthur called you a cheeky prat."

"Arthur was a clotpole so there."

I laughed as we walked further along the path. Growing up, Merlin had told me all about his life in Camelot. How he and Arthur had first met and hated each other. How they'd fallen in love. Apparently, Merlin said Arthur was going to get a kick out of me when I finally got the chance to meet him. Which was, of course, still three years away. In order to complete the past-time ritual Merlin had created, I had to be sixteen years old. Which meant that I had three more years of lessons before he could launch me thousands of years into the past so that I could right the wrongs. Most of these next years would be spent learning about the customs and traditions of Camelot during that time. I already knew nearly everything there was to know. Uther was an asshole. Arthur would most likely not believe me at first. Merlin himself would need to read the letter written by his future self. Gaius would need to read the letter himself. And Morgana would be quite eager to save her future. The knowledge helped but I was still a little nervous.

"Here we are. Kilghara should be here soon." Merlin said as he sat down.

"What is this place?" I asked, sitting next to him.

"Avalon Lake. Where Arthur is currently buried."

"Wow. Why does Kilghara meet you here?"

"No clue. He doesn't often answer my questions these days. Stubborn old dragon."

"Why are we here?"

"He wants to meet you. Something about your destiny."

Before I could reply, a large dragon dropped down in front of us. Kilghara. The Great Dragon. Last of his kind. He was a Speaker. The last one. There were other dragons but they didn't speak. They were beasts in every sense of the word. Kilghara, though, was sentient. A being with a more powerful mind than even Merlin himself. Merlin had told me many stories about him but this was the first time I'd ever met him. I had to admit that I was a little nervous. Merlin assured me, of course, that I needn't be nervous at all.

"It's been too long young Warlock." Kilghara spoke to Merlin, his deep voice echoing in my ears.

"That it has old friend."

Merlin's voice was solemn when he spoke, his young face showing his true age. Though he looked to be only a few years older than me, Merlin was over a thousand years old. Most times, his age didn't show. But at times like this, when he was faced with something from his past…his age was clearer than sun in the sky.

"And who have we here?" The dragon rumbled, looking down at me.

"Harry Potter." Merlin spoke my name with a grin and the dragon laughed.

"Ah so this is young Potter. I am very pleased to meet you."

"It's nice to meet you as well."

"He will change your destiny, Merlin." Kilghara's voice was full of wonder as he stared at me, his eyes bright.

"I know. I've known since he was only 6 years old. Took me two years to get to him, though."

"Do you know what you must do, young one?" Kilghara asked, turning his attention to me once again.

I nodded. "Merlin told me that I have to go back and warn them about Morgause. I…I have to stop Morgana from turning."

"And you realize that this may very well get you killed?"

Again, I nodded. "Yes sir."

"And yet…even with the risk to your life, you still choose to do it." The Great Dragon's voice was full of astonishment…as if I'd surprised him somehow.

"Merlin is my friend. The closest thing to a brother I've got. He's raised me, taught me, and protected me. I want to do this for him. He…he deserves it."

Merlin smiled at me. "I should also have mentioned that he's selfless. Entirely selfless. The boy thinks less of himself than of anyone else."

Kilghara rumbled a laugh. "You were much the same, young Warlock."

"Not really. I was selfish if anything. I protected Arthur because I couldn't imagine my own life without him. Selfish."

"Ah but you saved many others with no reason besides their innocence. Many would not have done the same, Merlin."

Merlin smiled. "I knew many that would. Gaius. Arthur. Gwen. Lancelot. Gwaine. They would all have done the same. Did do the same."

"I'm pleased with you Merlin. You have accomplished many great things and you will accomplish many more before your time is up. When young Harry here goes back…you will be faced with a great choice. A choice you will no doubt know the answer to without even thinking."

"What is that supposed to mean exactly?"

Kilghara simply blinked and smiled once more at us before launching himself into the sky. Grumbling, Merlin gave me a look.

"That. That is exactly what I meant when I said he doesn't often give me a straight answer to any question. Ever."

I laughed. "If he gave you all the answers, you wouldn't have to work for anything."

"That's enough of your cheek Potter. Let's go then. You have a Potions lesson with Severus in half an hour. I think he may have found a way to keep Dumbledore from finding you."

"All right then."

Merlin held out his arm and I grabbed onto it, wincing at the familiar sensation of Apparation. When we appeared back at the castle, Severus was waiting there for us with…


	3. Chapter Two

_A.N.: Hey guys! Sorry about the super late update. I've been really, really super busy. Thankfully, though, I've finally found time to update. You'll notice that I changed the ending to Chapter One, so I'd go back and just briefly skim the last line. Not a big change, of course, but a change. Anyways, I hope you enjoy and remember to review._

_TrueWinchester168_

**Chapter Two**

_Harry_

The lost portrait of Arthur Pendragon. I knew it was Arthur because, as soon as we walked in, he yelled Merlin's name. Back before his death, Merlin had created this portrait using magic. Someone had stolen it some centuries after Arthur's death and Merlin had been searching for it ever since. Severus had, as he tended to do, done a miracle and found it.

"Where was he?!" Merlin half-shouted at Severus who smirked.

"Albus Dumbledore's office, of course. Where are all lost things found?"

"That damned old coot!"

If it hadn't been for how angry Merlin was, I'd have laughed at his wording. Merlin didn't curse a lot, usually only when he was really angry. Behind us, Arthur cleared his throat. I turned to look at him. He was an attractive man. Blonde hair fell into sky blue eyes. His face was tanned and his body muscular. When Merlin met his gaze, the King raised an eyebrow.

"Must you shout _Mer_lin?" he said.

To someone that didn't know their story as I did, his tone would have sounded…rude. I knew it for what it was: relief. However long he'd been separated from Merlin had taken its toll on Arthur. He was happy to see his lover again.

"Yes. I must. He stole your portrait!"

Arthur rolled his eyes. "I'm back where I belong now, Merlin. That's what matters. Now, stop rambling about old coots and tell me what's been going on."

Merlin sighed, sitting in a chair in front of Arthur's portrait. "I've found a way to change the past, Arthur." He said.

"How?"

"I'm sending someone back there, someone that knows the full story. He'll stop Morgana from betraying us and he'll save your life. It's a long process but…it'll work."

Arthur thought about that. "It…sounds reasonable. Are you certain it's safe?"

"Of course I am. I've been working on it since your death. Harry, that's the boy I'm sending back, will be in absolutely no danger."

"All right then. When do you do it?"

"It'll be a few years yet. He has to be sixteen. He's only 13 now."

"Where is he? I want to meet this Harry person."

I stepped out from behind Merlin and faced Arthur. He appraised me for a few minutes before nodding.

"Why are you agreeing to this Harry?" he asked and I noticed that there was a note of genuine curiosity in his voice.

"I want to help Merlin. He's…miserable without you and he's done so much for me that I want to make that better."

"Even though it means leaving your world behind forever?"

"Well, like Merlin I'll be Immortal. Merlin created a spell that makes someone like him…Immortal. Merlin and I will live forever…and so will you when I go back. It's part of the reason why I have to be 16 to do this. He wants me to have reached maturity before he casts the spell. And besides that…this world isn't my world. I…don't feel as though I belong here. I've grown up Camelot...with Merlin. I'm not accustomed to the outside world."

Arthur nodded. "Then I can't wait to meet you."

I glanced at Merlin. "He doesn't seem like a prat."

Merlin laughed. "Just wait until you meet him in person. You'll see what I mean."

"I suppose I will."

Severus looked between us. "It's time for your lesson Harry."

"All right. It was nice meeting you Arthur. I'm sure I'll see you later."

"You as well."

As Severus and I walked away, I could have sworn I heard Merlin crying...


	4. Chapter Three

_AN: Hey guys! So this is short, I know. But I kinda meant it to be short. Harry is officially back in time! :) Now, I know you guys are wondering what happens with Merlin and Dumbledore and I'll show you as of next chapter. :) I hope you enjoyed and remember to review. _

**Chapter Three**

The next morning, after my usual classes with Severus and Merlin, found me sitting across from Merlin in his study. His study - bedroom that is - was Arthur's former bedroom. He'd hung Arthur's portrait up on the wall. Arthur appeared to be sleeping in his portrait, leaning against the painted armchair. Merlin was working on the spell that would send me back and muttering to himself when I entered.

"Hey Merlin?" I asked and he looked up at me.

"Yeah?"

"Why do you hate Dumbledore so much?"

He paused, setting down his quill. "Are you sure you want to know? It's not a nice story."

"Yes."

"When you'd first gotten to the Dursley's, I begged Dumbledore to let me raise you. He refused, of course. His pawn couldn't be raised by someone stronger than him. When I pressed the issue, he hid you from me. You were hidden for six years...but I kept having visions about you. Your uncle...was a very bad person. The things he did to you...Harry...I would have killed him that night had you not been in the house. I would have tortured him. That night, shortly after I located and took you, I went to see Dumbledore. I told him about the abuse you'd suffered, all of it. He knew. He'd known all along. He'd wanted you to suffer it...to harden you so that you'd become the perfect little pawn. We dueled...and I came back here. The next morning, you met Severus for the first time."

"He knew?! He...he knew what Vernon and Petunia were like?!"

"Of course he did." Arthur said from his portrait.

"How do you know?" Merlin asked, cocking an eyebrow.

"I was there. He and someone called Weasley were speaking about it. Marriage contracts and money and abuse. Terrible things. If I'd been alive I probably would have ran him through with my sword."

"What Weasley? There's a whole horde of them, you know." Severus, who must have been listening asked.

"Female."

"Molly then. She and Dumbleidiot must have been planning to marry Harry off to Ginny when he was old enough. Doesn't surprise me. That woman has always had a vindictive streak."

Merlin rolled his eyes. "Well, none of it will be happening now. In three years, Harry will be gone."

Severus sat down. "You'll want to change that. Do the spell to send Harry back now. Send him back further, to when Uther was alive."

"Why?" Merlin asked.

"Dumbledore has located you. You've got to hurry. Send me with Harry. I'll go and protect him. We'll bring your Immortality spell with us. You can perform it when he's of age."

Arthur's portrait paused. "My father was not a very agreeable man. Magic was outlawed." he said.

"I've got a letter for Harry to give Uther. It'll explain everything. Harry can also give an oath if Uther wants. Whatever keeps him alive without keeping secrets."

"Hurry!"

Merlin stood up and faced Severus and I. Pulling me into a hug, he reached out a hand and whispered a goodbye before sending his magic hurtling into us. He whispered three words that I didn't recognize or know and we were flying suddenly, flying backwards through time. As we flew back, I heard an old man scream.

We hit the stone floor in the same room we'd left. It was different this time, though. Arthur himself stood next to an astonished Merlin. I nearly dropped to my knees in the middle of the floor but Severus kept me standing up.

"Who are you?!" Arthur demanded and I pulled the letters out of my pocket where Merlin had stuck them.

I handed one to Arthur and one to Merlin and watched them read. Merlin finished first, his gaze wide and shocked. When Arthur finished, he was shocked beyond belief.

"You die...Arthur..." he whispered.

"No he doesn't. Not this time around." I said and Merlin turned his eyes to me.

"How do you plan on stopping it?"

I rolled my eyes. "Merlin, read your letter again. You sent me back with instructions to keep Morgana from going evil. It was either you kill her - you failed - or she goes evil. We have another choice now. I'm going to save Arthur. I promise you."

"Bloody Hell..."

Arthur fainted just as Uther walked in...


	5. Chapter Four

**Chapter Four**

"What is going on here?!"

"Uther Pendragon?" I asked, my voice steady but my hands shaking.

"Yes of course. I'm the king. Who are you?"

"I'm Harry Potter. This is Severus Snape. We need to speak with you, Merlin, and Arthur alone. Now."

Uther's face tightened. "I don't give conferences to strangers."

"Sir, this is about the life of your son. What I have to show and tell you will change the future."

He stood silently for a few moments, warring with himself. As he battled internally, Arthur woke up. The young prince stood and placed himself between his manservant and Harry discretely, looking as though he'd attack at the first sign of danger. As he did this, Uther came to a decision.

"We're all gathered here. Might as well shut the door and get this over with."

He shut the door and Harry quickly - but wandlessly - cast a Privacy Charm around the room. As he did that, Severus slipped a letter into Uther's hand. Uther read it quickly, his eyes widening as he read it. When he was done, he turned and demanded an explanation.

"How do you know all that?!"

"Merlin told me. Well...Merlin from the future which is where we're from. He's...desperate to change things. For the better."

At that, Merlin finally spoke up. "What do you mean? How do things end up?"

I took a deep breath, looking at Severus. He nodded once and I decided to tell them what would happen.

"Morgana betrays you. It's...difficult to explain but she's used by someone called Morgause to kill Uther and eventually take the throne. She never gets that far...but Mordred does kill Arthur. Mordred is a druid warlock who allies himself with Morgana. After he kills Arthur, Merlin kills both of them and...well he spends the next thousand years alone. Until me."

Merlin's face is white and Uther looks like he's going to scream. Or cry. Or explode.

"How did you come back?" Uther demanded and Severus stepped forward.

"Magic. Before you say anything, however, I'd like to say a few things on the subject."

"If what you say is correct, you will save my son. I will allow you to speak."

"Thank you sir. The magic we use...and the magic Merlin himself possesses...we are born with it. We use it only to help others...and also to do small household tasks. It is not used for evil. It's...actually against our laws."

Uther's face tightened and we waited for a reply. Would he sentence us to death or would he accept our help?


End file.
